Selective cellular probes for mammalian thioredoxin reductase TrxR1: Rational design of RX1, a modular 1,2-thiaselenane redox probe
Year: 2022
Type: article
Abstract: Cellular redox networks power a multitude of cellular processes, and are often dysregulated in pathologies including cancer and inflammatory diseases. Quantifying the turnover of the key players in redox homeostasis is crucial for understanding their physiological dynamics and for targeting them in pathologies. However, suitably selective probes for assessing specific redox enzyme activities in cells are lacking. We rationally developed the first chemical probes targeting the mammalian selenoprotein thioredoxin reductase (TrxR) while fully resisting other cellular thiols and oxidoreductases. We used a cyclic selenenylsulfide as a thermodynamically stable and kinetically reversible trigger, oriented to harness the chemistry of TrxR's unique selenolthiol active site, and integrated it into modular probes releasing arbitrary cargos upon reduction. The probes showed remarkable selenocysteine-dependent sensitivity to cytosolic TrxR1, against a panel of oxidoreductases. Lead probe RX1 also had excellent TrxR1-selective performance in cells, as cross-validated by TrxR1 knockout, selenium starvation, TrxR1 knock-in, and TrxRselective chemical inhibitors. Its background-free fluorogenicity enabled us to perform the first quantitative high-throughput live cell screen for TrxR1 inhibitors. This indicated that tempered SNAr electrophiles may be a more favorable drug class than classically-used electrophiles. The RX1 design is thus a robust, cellularly validated, high-performance modular system for mammalian TrxR1. This sets the stage for in vivo imaging TrxR1 activity in health and disease, and can also drive and reorient TrxR1-inhibitor drug design. The thermodynamic and kinetic considerations behind RX1's selectivity also outline paths towards rationally-designed probes for other key players in redox biology.
Source: Chem
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
Funders: Verband der Chemischen Industrie, Joachim Herz Stiftung, Swedish Cancer Foundation, Deutsche Forschungsgemeinschaft, Bundesministerium für Bildung und Forschung, Cancerfonden, Karolinska Institutet, Knut och Alice Wallenbergs Stiftelse, Studienstiftung des Deutschen Volkes, Vetenskapsrådet, Ludwig-Maximilians-Universität München, Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, Centre for Nano and Soft Matter Sciences, National Institutes of Health, National Center for Advancing Translational Sciences
Awards: G1242026511, G1579701519, Photo/photoredoxschaltbare Liganden als chemische Werkzeuge für die Optogenetik, Chemische Methoden zur Charakterisierung sowie Kontrolle des Mikrotubuliaufbaus und der Mikrotubulidynamik unter physiologischen Bedingungen, G3354437248, G388153354, G3916100709, SFB 1032: Nanoagenzien zur raumzeitlichen Kontrolle molekularer und zellulärer Reaktionen, TRR 152: Steuerung der Körperhomöostase durch TRPKanalModule, G899191640, G9000039905
OpenAlex ID: W4226143764